Marking compounds, such as fluorescence markers, are routinely utilized to mark hydrocarbons, such as fuels. When such marking compounds are utilized in hydrocarbons of varying composition, the marking compounds can sometimes undesirably exhibit variable response (i.e., variable intensity) without any noticeable changes to analytical results, such as spectral shape or wavelength. In such instances, standard chemometric models may not adequately handle quantification of the marking compounds.
Accordingly, there exists an ongoing need for methods of improving the accuracy when quantifying marker compounds, such as fluorescence markers, in hydrocarbons, such as fuels, as will be described in more detail hereinbelow.